How To Create A Bootable Clone Of Your Mac Hard Drive

Mac’s come with a built in tool called “Disk Utility” which can be used to clone your Mac Hard Drive. The process of creating a bootable clone of your Mac Hard Drive is fairly simple, but before we get into the nitty gritty of actually creating a bootable clone of your Mac Hard Drive, lets talk a little about the reasons and advantages behind doing this.

1. Great Way To Have A Functional Backup Of Your Entire System

By cloning your Mac Hard Drive, you are essentially creating a exact copy or backup of your entire Mac system, this includes Operating System files and the Users home directories. Not only that, since this is a exact copy of your Mac Hard Drive, you can even boot of the Clone Drive by simply having the Clone Drive plugged in and keeping the Options key pressed down during system boot-up.

2. Useful In Testing Applications And Trouble Shooting Issues

The Clone Drive can be used to test new applications or software updates before actually installing it on the primary system. Also, in case of a system problem, you could boot of the Clone and identify if the problem is software or hardware related.

3. Ready To Go Replacement Of The Primary Hard Drive

In case of a Hard Drive failure or corruption, you could be crippled for hours or even days before the primary Drive could be fixed and data restored. Instead, you now could be immediately back in business by simply booting of the Clone Drive.

Using Disk Utility To Clone The Mac Hard Drive

Okay, now that we have discussed the reason behind cloning your Mac Hard Drive, lets actually see how to do it. Every Mac comes with a built-in tool called “Disk Utility” has mentioned earlier, this is what we will use to clone your Mac Hard Drive. You will also need an external Drive. Make sure that the external Hard Drive you are using for this purpose is equal to or larger than the used space on the source Hard Drive you plan to clone. Also, make sure to backup any data on the external Hard Drive, since all data on the Drive will be erased.

Now with your external Hard Drive plugged in and “Command” Key and “R” Key pressed down power-on your system. This will boot your system in Recovery mode. The reason you do this is, since you are cloning your OS partition you do not want anything from being changed on the source Hard Drive, booting your system in Recovery mode achieves this. Once in Recovery mode, Launch “Disk Utility”.

Once in “Disk Utility”, select the OS partition from the left hand pane, which is usually the first partition under the first Hard Drive in the list. Then, click the “Restore” tab on the right hand pane. Here you should see your OS partition already selected in the “Source” box.

Next, select the target partition on your external Hard Drive, on which you want to create the clone, from the Left hand side pane and drag it to the “Destination” box. Once the target partition shows up in the “Destination” box, hit “Restore” and the cloning process will begin. Once complete you should have a fully bootable replica of your OS partition / Mac Hard Drive.

Assumption: Please note, that this article assumes you have a Mac Hard Drive with a single partition / volume. In case you have multiple partitions on the source Hard Drive and want all partitions cloned, then make sure to partition the target Hard Drive to match the partition structure of the source Hard Drive. For help with partitioning see my article “Partitioning A Hard Drive On Mac Running OS X Lion“. Once you have created identical partition structure on the target Hard Drive, you can clone each partition / volume using the method described above. Except OS partition, all other partitions can be clone while logged into the system.

It’s as simple as that. If you want to boot into your new clone, simply have the external Hard Drive connected and keep the “Options” key presses down during boot-up and select the Clone. Also, in case you want to restore a specific file from the clone, you could always access it from “Finder”, just like you access any external Hard Drive. And in case you have an unfortunate event like a Hard Drive failure or corruption, simply reverse the above process to restore the Clone to a new Hard Drive.

Update (30th March 2013): This article has been modified for clarity and to ensure accuracy.

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About Vijay

Computer junky for 20 plus years and still obsessed with it. I enjoy exploring and tweaking popular operating systems and tinkering with computer hardware. Professionally, I work as a Storage Systems Administrator. When not on my computer, I love to travel, shop, read and hang out with my family and friends.

Comments

I found your blog very informative and unique from others, the way of expressed your ideas is appreciable. I used to Clone Mac regularly in order to protect my vital data from losing. We should make bootable clone of our drive ,so that in situations when Mac is not bootable,we can boot our Mac using bootable clone of our Mac OS.

Quick question: I want to clone my Mac hardrive, but as a backup…..Incase something does happen to my current computer and I end up getting a new one…Will I be able to restore it ‘identically’?

“Also, make sure to backup any data on the external Hard Drive, since all data on the Drive will be erased.”

Since stated that you’d have to erase everything you’d be transferring….Just wanted to clarify if that was the only way! I already back up some things on my ex-hardrive but i wanted to back up the whole shabang….

Yes, you can clone back from the external drive (original destination) back to the internal drive (original source). Just remember that the clone is a point in time image of your internal drive and not a up to date copy. So, any changes you do to the source after cloning will not be available after on the clone. I would recommend Time Machine backup, if you are interested in maintaining a true and up to date backup of your system.

Also while cloning, the destination partition is completely erased and written with data from the source partition, which is why I suggest taking a backup of the destination drive if you have data on it. hope this clarifies things.

Regarding “Make sure that the Hard Drive you are using for this purpose is equal to or larger than the source Hard Drive you plan to clone.”, can you clarify on that? is it that the Destination drive has to be larger than the Disk usage on the Source drive (and not the capacity of it)?

Correction: Hi Chase, I did some more testing on this topic and found that you can actually use a smaller destination Drive than the source Drive, provided the destination Drive is larger than the used capacity on the source Drive. Please note, you are cloning the partition and not the drive itself. Also, I have made changes to the article to reflect the same.

Quick question: You mentioned “Make sure that the Hard Drive you are using for this purpose is equal to or larger than the source Hard Drive you plan to clone.”
What can i do if I am trying to swap the 1TB HD with a 240GB SSD? The MacMini is new, so there is much less data than 240GB on the original HD. Is the HD capacity (i.e. 1TB) or the amount of data in the HD (much less than 240GB) key factor in this?

Correction: Hi Ahmet, I did some more testing on this topic and found that you can actually use a smaller destination Drive than the source Drive, provided the destination Drive is larger than the used capacity on the source Drive. Please note, you are cloning the partition and not the drive itself. Also, I have made changes to the article to reflect the same.

Hello Vijay,
I am in a similar situation.
I have a 500 GB HD Macbook Pro that I am giving to my son for High school graduation
and he is using my “old” iMac 640 GB HD(early 2009 intel core Duo).
I’d like to clone my McBook Pro HD into the internal iMac HD, to keep all application intact.
I have clone my McBook Pro drive to external but it is too slow when booting from it via fire wire 800.

Apple Genius recommended using Migration assistant but every time I’ve used it , some third party application will not work and I have to reinstall .

Do I need to partition the iMac to two part ions(500 GB and 140 GB)?
Genius said I may have problems because of the 140 GB partition was too small for OS
What do you think?

I am a little confused. So if I got this right, you are trying to clone your new 500 GB MacBook Pro HD to the older 640 GB iMac HD correct? Also, when you say your external HD clone is booting up slowly, which system was it connected to?

Also, just to clarify 140 GB is more than sufficient to run any OS available today, so not sure what the Genius meant with that remark. Partitioning your iMac Drive might help improve performance slightly but your bottle-neck is the interface. If you really want a quick machine, internal SSD is the way to go.

Vijay,
Thanks for the prompt reply.
The iMac is a ~ 2 Yrs Old Intel Core Duo with $ GB Ram and a 512 Video Card and a 640 Internal HD.
I cloned my Macbook Pro into a 500 GB external HD and boot my iMac selecting the External (Cloned HD from Macbook Pro) using the fastest cable I had which was the firewire 800.
I’m assuming that if I clone the Macbook Pro 500 GB HD into the 500 GB Partition of the original internal iMac 640 HD (two partitions 500GB and 140 GB) the booting would be much faster.
This is assuming that in order for me to clone my 500 GB Macbook Pro HD,
I need to clone to an equal or bigger HD (but if larger that 500 then I need to partition the HD to create a partition of equal size).
Or can I clone using the MacBook Pro 500 GB as a source and the iMac 640 GB as the destination without partitioning the iMac HD First?
I hope this time I did a better job at explaining.
Thanks in advance.

Yes you did :). So, to clone a drive A to a drive B, drive B only needs to be bigger than the total used space on drive A. So in your case, you can clone the MacBook Pro drive to the iMac drive with out partitioning it. But if you do decide to partition it for other reasons, that also okay as long as the earlier condition is met. Note, make sure to backup your contents before you start. Hope this helps.

Vijay,
Thanks so much for your prompt responses.
I was able to clone my MBP into the internal HD of my iMac with no problems.
I also made an external clone to an external HD in a firewire 800 enclosure.
before I clone I made sure my source HD was healthy by using Drive Genius which return a corrupted HD that it was not able to repair, so I had to use Disk Warrior to fix it then I went back to Drive Genius to verify and defragment.
I am, very glad I found this blog and your help, once more Thank You Vijay.

Vijay, hello. I tried to follow your instructions (I have a mid-2009 MacBook running 10.8.2) and all was as you described except the hard drive I want to clone is grayed out and won’t move into the Source box. Any idea why and how I can fix it?

Correction: Hi Mike, you actually have to select the source partition and not the physical drive in the source box. Also, if you have a encrypted source partition, you will have to unlock it by entering your password.

Let me explain what I need to do, I wish to replace the current Maxtor 1TB hard drive that is currently installed in my Mac Pro tower with a Western Digital 1TB or 2TB hard drive. Mac OS X Version 10.7.5 Lion , Microsoft Office Mac for Home / Business, Photoshop CS5 Master Collection, & several other Apple / Mac add on programs are installed on the original hard drive. I am worried that the Maxtor hard drive is going to eventually cause me some issues, mainly because it is a company I do not know or trust since now it has been bought out by Sea Gate.My question is, will everything including all my installed programs to the new Western Digital hard drive? Or will I have to reinstall all the specialty programs ? The latter would be a pain, because I would have to locate the installation serial code keys.

Hello George, no you should be fine and should not have to reinstall anything. However, just to be double sure, I would strongly recommend that you do not get ride of your old drive till you have tested your new drive for a week or two and made sure everything works without a problem.

So everything I have on the original HDD will clone to the new HDD. Will Disk Utility do this easily or do you advise a better, foolproof software. I’ve been reading up on the SSHDD’s with the thought of the OS & all my peripheral software on the SSHDD with a 2nd HDD for all my storage. The Mac Pro’s have room x4.
Thank you
GTK

On my computer, I left my user folder on my SSD, but I made Documents, Downloads, Movies, Music, Other Data (my catch-all place for data that doesn’t really belong in Documents), and Pictures symlinks to folders equivalent folders on my HD.

I found your blog and I expect it is not too late to ask you a question. Is it possible, by using the method described, to transfer the exact contents of my iMac HD to my new Mini Mac? And expect the Mac Mini to run, naturally. Thanks in advance if you are able to answer.
JAFC

To be honest, I haven’t tried doing this on Mac OS X. In the linux world this works only if all of the new hardware is compatible with the OS. However, with Windows this might not work. I personally would re-install the OS on a newer hardware to be sure I do not run into minor issues later on. You could always experiment this on a external drive and see how well it works before you actually get ride of your old system. Note, I am only referring to the OS partition here. Moving Data partitions should not be a problem. Let us know how it pans out.

I read your whole post and want to share my cloning software that I have been using from two years. Although Disk utility is great in verifying and repairing permissions but for cloning I prefer to use Stellar Drive Clone software , a third party utility having many great features and easy to use interface. This software is capable to create bootable clone of your Mac drive and image of your drive,volume.

I’ve never heard of this before. I used to use “asr” (Apple System Restore) but it’s become rendered somewhat lame over the years.

A word of warning to users though: If you’re cloning your drive because you think it has problems, you might want to test it and make sure it’s actually good first. I’ve seen cloning copy bad sectors or corrupted indices right over to a cloned drive and instead of correcting a problem it’s just transferring them. Disk Utility can do some basic index repair, but if the problems are severe, you might need something like Disk Warrior. Likewise if the surface of the drive is bad, you might want to test it with some of the tools that can do that like Scannerz, Disk Warrior, or Tech Tool Pro.

I will definitely have to try this out. “asr” was a command line tool and was a bit clunky, IMHO. This is slick.

Hi Jeremy, newer hard drives usually have the ability to scrub for bad sectors and fence them off. So, cloning should not transfer them over. Just to be on the safe side, I would check my disk for errors after the cloning is complete.

Correction: Hi Markus, I did some more testing and found out that cloning won’t encrypted the target drive. Also, to be able to clone a encrypted Drive you will first have to unlock it by entering your password.

I found this comment on another web page. “Normally I’m used to simply mirroring the old drive onto the new one during an upgrade, but with OSX Lion and later, Apple installs a hidden Recovery HD partition.This hidden partition is essential for running OSX, and will be lost if you use disk utility to do a direct copy of the old drive.” Does your method install the Recovery HD Partition?

Correction: Hi Eddie, after some additional testing I have found that the Recovery HD partition is not being copied over with Mountain Lion. But it used to work in the past, not sure what has changed with ML release.

However, you do need Recovery HD for the OS to function. It is only required to boot into Recovery mode.

Hi Eddie, I ran into the same issue. There are two ways to recover the recovery partition. After you just use Vijay’s steps and you end up with the cloned drive (without recovery partition) you can run the MacOS setup from within the operating system. It will look like a normal setup, but in the end it will only refresh OS files, all your folders and MacOS settings stay in tact. Of course if you installed Lion or Mountain Lion using the Appstore, you should download the OS from there and not install from a DVD with the older OS.

The second option is much faster and easier. I downloaded a program called Carbon Copy Cloner. The first month it has a fully functional trial. The program has an option called “Restore recovery partition” and it will do just that. I have tested it several times successfully myself. Just takes a few minutes, at least on an SSD.

Hi Smith, yes there has been a lot of buzz about hybrid drives lately. Although I haven’t personally used one of these, I don’t see a problem cloning to it. As long as Mac OS X is able to detect the drive, the type of drive shouldn’t matter.

Hi Vijay,
I follow the steps, because I am upgrading my macbook from a 256gb to a 512gb ssd. The idea is to clone, then extend the partition from 256 to 350 and use the remaining 150+ as exfat for Windows 7 through Bootcamp.

However, after going through the above steps I ended up with a 512gb drive with the full clone, but the clone takes up all the 512gb, instead of 256 that the original drive size was. Going back to disk utility the utility does not allow me to shrink the partition, instead it ownly allows me to create two partitions by deleting the current data on the drive.

Hi Wouter, disk utility should let you split the drive after and adjust the size to what you desire. If not you can always partition the drive to 350 GB and 150 GB before you clone to the new drive. Make sure to drag the 350 GB partition to the destination box.

Hi Vijay,
I got it to work. Big shame for me on what caused this behavior. When you want to change the partition size and change the number in the box, the button for apply stays greyed out. But if you type the number of the new size and hit enter then the “apply” button turns on. That is the kind behavior I would expect from my windows computer

I cloned the drive and got the multi boot windows setup to work. There is some interesting behavior though that in the end got me to have to reinstall mac os on top of the new installation. When you clone a drive you can select the actual drive or the partition on the drive. I chose the partition, because on drive level the restore tab was not available. The downside of that is that the Recovery partition is not going to the new destination drive and without a recovery partition you cannot turn on filevault.

The way to get that partition back is reinstalling mac os on top, just run the setup and all other files stay in tact, this will create a new recovery partition. The Apple care guys were not sure if it would go right, since there was also a windows partition. What the MacOs setup does is shrink the OS partition by 1 GB if there is not enough space left for the recovery partition and then put the recovery partition back in its place. Copying the recovery partition manually to the drive is not an option, because MacOS will not recognize it as the recovery partition it just shows it as an extra partition (meaning it won’t respond to startup with CMD-R). My safeguard was that before I ran the MacOS setup I just shrunk the main OS partition by 1 GB myself so there would be enough space of unpartitioned space for the MacOS setup not having to decide which partition to shrink to make space.

The last weird issue I am running into. The setup is as follows:
– 512 ssd (now in my macbook as new drive with multiboot)
– 256 ssd on usb controller (original ssd that still has the full OS from the previous setup with filevault, including recovery partition)
– 512 hdd on usb controller fully empty with one partition

The only thing I want is copy the 256ssd usb to the 512hdd usb, to have an emergency bootable external drive to continue working if anything would happen to the 512ssd. But when I click the 256ssd I don’t see the Restore tab on the drive level, only in partition level. Because of that I cannot copy the recovery partition to the other drive and without that partition the backup will not be encrypted.

Weird thing is that the 512hdd on usb does show the Restore tab. Also the icons are different in disk utility. Even though both are connected at the same time through USB, one shows as a USB disk and the other has an icon as if it is an internal drive (orange icon for USB, grey metal hard drive icon for 256ssd usb).

Well, I can imagine if this doesn’t make sense to you either, but worth a shot to share.

Hi Wouter, with all the great questions and feedback I have been getting from my readers I decided to do some more testing. So, I did see that Recovery HD is not being copied over with Mountain Lion. I am pretty sure it used to before, since my earlier cloned OS partition was showing Recovery HD. Also with ML, I see that I need to unlock my FileVaulted partition before I clone it, resulting with an unencrypted clone. Again, I am pretty sure that wasn’t the case before. Also, if you notice the way partition structure is displayed in ML differs from that with Lion.

Referring back to your question, as you have realized, you can only clone your partition and not the drive itself and you also need to unlock any encrypted partitions. The reason why your USB Drives show up with different icons is probably because one is encrypted and the other isn’t.

Hi Vijay,
Any thoughts on why I am getting the “Invalid Argument Error 22″ message when I try to initiate the clone in Disk Utility. I entered everything in the Source and Destination field just like you did, but when click Restore, the above error message appears. Paul

1. Are you trying this while logged into the system or from recovery mode? You should always do this from recovery mode.
2. Is the destination drive formatted to work on a Mac? Especially if that was not the factory default.
3. Is the source or destination drive encrypted. Note, if you have file vault enabled your source drive will be encrypted. In which case you will have to unlock it using you logging password.

3. I assume it is formatted to work with a Mac since I have been using it up to now with Time Machine. In fact, this is the reason I decided to try cloning instead of incremental backups because the Time Machine filled up the back up on the second run.

4. I don’t think either one is encrypted, but I am not sure what Time Machine does on its own. I have been a PC guy for 20 years, so this is my first Mac computer, and hence my first backup attempt, which means I don’t know a lot about Apple gear yet.

Hi Paul, You can work around Time Machine filling up your drive, by turning of auto back-up and doing it manually. I actually was planning on blogging about this in my next article this week, so stay posted. Will check on the actual error and get back, have been a little busy re-designing the site :). In case you wanna do it yourself, apple forum is a great place to start.

Hi Paul, I was able to do some addition testing and although I wasn’t able to reproduce “Error 22″, here is what I found. You can actually clone from a larger Drive to a smaller target Drive provided the used space on the source Drive is smaller than the size of the target Drive.

Also, you need to select the actual source and target partition you intend to use for cloning, since selecting the entire source and target physical Drives itself will error out. Which means you will have to clone each partition separately to clone the entire Drive. I have edited my article to explicitly imply the same.

P.S: I have removed some of our earlier discussion regarding Time Machine backup to maintain flow.

Hello Vijay, it’s a very clear and nice instruction. One quick question: if the mac hard drive has 500GB while the usb external drive has 1TB, after cloning the mac hard drive to the external drive by Disk Utility, can I restore back the image from the external drive to the mac hard drive since the external drive is bigger than the mac hard drive?
Or should I partition the external drive to 500GB before cloning?

Hi Alex, I was able to do some rigorous testing on this topic and contrary to my assumption, you can actually clone and restore from a larger drive to a smaller one as long as the actual used space is smaller than the destination drive. Also, I plan on posting a detailed article on my findings shortly, so stay posted.

On MBPro 2009 and a MacAir 2011 OSX Mountain Lion, I get the message “Restore Failure could not validate source – error 254″ any Ideas? External is larger or = to the internal drive size. I also have a gray line below both showing the USB external drive on the left:
______________________________
Disk1
Mac OSX Base System
160.4 GB Generic External
Untitled

Hi Rob, I was able to recreate the error. So, looks like the images in this article might have miss led you (which I will fix ASAP). Let me explain. In the images above I selected the actual drive and not the partition under the source and destination drives, which is what is causing the error. So while clonning you need to select the source partition and the destination partition, doing this will resolve your issue.

Also, if you are clonning your OS partition, it needs to be done from recovery mode, otherwise it will error out. Data partitions can be cloned while logged in.

I just did a swap out of a new HDD with my 2009 Macbook using these instructions. Using the Disk Utility worked flawlessly. Everything went super smooth on the first try. Thanks for posting this to help everyone.

Vijay ; I explained what I wanted to do with my Mac Pro Tower in a comment a few weeks ago. I think I will start off my projects with my late 2011 / early 2012 MacBook Pro 15″.
It has a Toshiba 500gb hard drive with OS Lion on board. The only changes I have made was the upgrade to OS Mountain Lion & Office for Mac. I have purchased a Samsung 840 Series 500gb SSD manufactured late 2012 & should have the latest firmware on board. What is my best choice ? doing a clean install of OS Mountain Lion & Office after formatting the SSD to Mac, or doing the clone with Disc Utility. How should I set up the partitions ? Will the clone duplicate the partitions of the original drive ? I do have an external HDD enclosure to use & the advantage of not having much on the original HDD. Will the Mac format wipe the firmware ? I have read the only Windows based machines can download the Samsung firmware. I need a step by step foolproof instructions to make this go right.

Hi George, I think cloning will be the easier option for you. I am not so sure what will happen to the firmware level though, you could check with Samsung or post the question on Mac forum. As far as the steps are concerned, below is a gist of it;

1. Connect your new Drive using the Drive Enclosure and replicate the partition structure to match the source Drive. See my article on partitioning for details. Again this is required only if you have more than one partition on the source and want to clone them all.
2. Reboot into Recovery mode by keeping the CMD+R key pressed down during boot-up.
3. Once in Recovery mode. Clone each partition as described in this article. Note, while cloning make sure to select the individual partitions and not the Drive itself. Also, any encrypted partition need to be unlocked first. You can do this by clicking on the unlock icon and entering your password.